Metal complexes, clathrates

An interdisciplinary approach should lead to their future prospects as building blocks of a variety of chemical structures. Thus, betaines 1 can be incorporated as a subunit(s) in host molecules and could confer unusual properties to the supramolecules, either cavitates or clathrates. Their capacity for specific physical behavior should also be considered together with their use as neutral ligands (azolate ligands without counterion) in forming metal complexes. Advances in the chemistry of betaines 1, to be of any real significance, must result from coordinate efforts directed toward supramolecular chemistry, advanced organic materials, and heteroarene coordination chemistry. 

The compounds form chiral metal complexes as well as chiral clathrates and can be used as auxiliaries for asymmetric syntheses [64]. 

So-called Werner clathrates are another prominent series of clathrate compounds formed between a metal complex host and an aromatic guest molecule. The name Werner originates from A. Werner, who established the coordination theory of metal complex compounds. The host of the series has a general formula [M(NCS)2(4-Mepy)4], and in fact, the series is obtained conceptually by replacement of C N and NH3 in the Hofmann-type host by SCN and 4-Mepy (4-methylpyridine), respectively. This was done in order to increase the inclusion capability for bulkier substituted aromatic molecules, in particular, those related to the petroleum industry. 

Iwamoto, T. Kiyoki. M. Malsuura, N. Thermally stable cyclohcxadicnyl radicals produced in the benzene clathrates with metal complex host latices. Chem. Lett. 1975,... 

Nishikiori. S. Takahashi-Ebisudani. Y. Iwamoto, T. Novel series of clathrate compounds of the three-dimensional metal complex hosts (yV-methyl-l,3-diaminopropane) cad-mium(II) tetracyanonickelate(II), (V,V-dimethyl-1,3-diaminopropane) cadmium(II) tetracyanonickelate(II) and (2-hydroxyethylinethylamine) cadmium(II) tetracyano-nickelate(II). J. Inclusion Phenom. Mol. Recognit. Chem. 1990, 9(2), 101-112. 

The host metal complex has the three-dimensional structure consisting of the two-dimensionally extended cyanometal complex sheets and of the 1,4-diaminobutane ligands bridging adjacent sheets at the respective Cd atoms in the sheets. The Cd atoms are alternately linked with the square-planar Ni(CN)i moieties at the N-ends at each Cd-N junction the metal complex network bends to give a wavy structure of the sheet similar to those observed for Hofmann-mea-type pyrrole clathrate [14] and Hofmann-dma-type ones [8,9]. 1,4-Diaminobutane takes a trans-cis conformation of its N(3)-C(3)-C(4)-C(5)-C(6)-N(4) skeleton on the mirror plane at y=l/4 except the C(5) which is distributed statistically at both sides of the mirror plane the positions of hydrogen atoms attached to C(4) and C(6) atoms have been calculated in relation to both the... 

THREE-DIMENSIONAL METAL COMPLEX HOSTS BUILT OF a, a)-(LONG-CARBON-CHAIN)-DIAMINOALKANE LIGAND BRIDGING TWO-DIMENSIONAL CYANOMETAL COMPLEX NETWORK HOFMANN-DIAMINOALKANE-TYPE CLATHRATES... 

We have been developing systematically the chemistry of Hofmann-type and related clathrate compounds. Several modifications of the metal complex host structures have been derived from that of the Hofmann-type by replacing the ammine ligands by amines or diamines, and/or the square-planar tetracyanometallate by tetrahedral one [1]. However, their structures were substantially similar to that of the Hofmann-type the volume of cavity was barely large enough to accommodate such small aromatic molecule as those enclathrated in the Hofmann-type host. 

Recently three-dimensional metal complex hosts have been developed from the two-dimensional Hofmann type host lattices, M(NH3)2Ni(CN)4, by replacing the ammonia groups by bidentate ligands, with the aim of enlarging the range of guest molecules which can be accommodated in the host lattices [1-5]. In a previous study Mathey et al. reported the preparation of the Ni(4,4 -bipyridyl)Ni(CN)4 host lattice and its benzene, xylene, naphthalene and anthracene clathrates [5]. We have extended this study and prepared M(4,4 -bipyridyl)Ni(CN)4-2G (M = Ni or Cd G = dioxane, toluene, aniline or iV,AT-dimethylaniline) clathrates for the first time. In this study an IR spectroscopic study of the M(4,4 -bipy)Ni(CN)4 -MG compounds (where M = Ni or Cd, G = dioxane, benzene, toluene, aniline or iV,AT-dimethylaniline, n=0-2) (abbreviated henceforth as M-Ni-bipy-G) are reported. Additional information is obtained from the laser-Raman spectrum of the Cd-Ni-bipy complex. We also recorded the powder X-ray diffraction patterns of the M-Ni-bipy complexes. 

An enormous variety of solvates associated with many different kinds of compounds is reported in the literature. In most cases this aspect of the structure deserved little attention as it had no effect on other properties of the compound under investigation. Suitable examples include a dihydrate of a diphosphabieyclo[3.3.1]nonane derivative 29), benzene and chloroform solvates of crown ether complexes with alkyl-ammonium ions 30 54>, and acetonitrile (Fig. 4) and toluene (Fig. 5) solvates of organo-metallic derivatives of cyclotetraphosphazene 31. In most of these structures the solvent entities are rather loosely held in the lattice (as is reflected in relatively high thermal parameters of the corresponding atoms), and are classified as solvent of crystallization or a space filler 31a). However, if the geometric definition set at the outset is used to describe clathrates as crystalline solids in which guest molecules... 

Pb azide, Pb nitrophenols, Pb triethanol-ammonium perchlorate and PETN or RDX, with a sheath spun from filaments of a thermo plastic material or a ductile metal such as bronze) Ad 159) J.F. Kenney, USP 3293091(1966) CA 67, 7089(1967) [Primary expl mixts contg 46% of complex clathrate inclusion salts (as shown by X-ray diffraction data) of basic lead picrate, such as Pb(C5H2N3O7)2-Pb(OH)2-Pb(N03)2.-Pb(OAc)2, 50% Ba nitrate 4% Tetracene]... 

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